Overflow drain

ABSTRACT

An overflow drain cover assembly includes a weir that enables a fluid level in a container to rise above the bottom of an overflow drain in the container. The weir covers all or a portion of the overflow drain and has a cavity portion between the weir and the overflow drain. The cavity portion is open at the top of the weir so when the fluid level in the container rises above the top of the weir, fluid can flow over the top of the weir and enter cavity portion and thence into the overflow drain.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to plumbing fixtures. In particular, the invention relates to an overflow drain in a container.

2. Description of Related Art

The inner volume of a bathtub or sink is defined by a plurality of vertical walls. One of these walls includes can include an overflow drain opening formed therein. When water is added to the bathtub, the overflow drain prevents the bathtub from overflowing by providing an outlet for water at a level near the top of the bathtub. Conventionally, the overflow drain is a pipe having a known diameter to enable contents to flow out of the bathtub or sink at least as fast as a predetermined rate.

A cover or escutcheon is used to conceal the overflow drain for at least aesthetic purposes. The plate covers all or part of the overflow drain and may have holes therein to permit water to enter without completely sealing the overflow drain. These plates or escutcheons typically are designed to cover overflow drains virtually in their entirety, but include an opening in a lower portion. The opening enables water to exit the bathtub and enter the overflow drain.

When a person enters a partially filled bathtub or items are put in partially filled sink, water is displaced and the water level rises. This displacement can cause the water to rise to a level higher than the overflow drain. When this occurs, water channels through the plate opening and exits the tub through the overflow drain. The water level is thereby maintained at a maximum level that is no higher than the lowest portion of the overflow drain. That is, the vertical location of the bottom of the overflow drain along the vertical wall of the tub, therefore, determines the maximum height of the water level in the bathtub.

SUMMARY OF THE DISCLOSURE

In one aspect of the invention, an overflow drain cover assembly includes a weir having a cavity portion. When mounted to an overflow drain on a substantially vertical wall of a container, the cavity portion forms a first gap at a top of the weir. The weir blocks contents of the container below the top of the weir from entering the overflow drain. A first cross-sectional area of the first gap is a minimum of 1000 square millimeters.

In another feature, the overflow drain cover assembly has a gasket between the weir and the vertical wall, the gasket enhancing a seal between the weir and the vertical wall when the weir is mounted to the overflow drain. A cover covering the weir and having one or more openings on a bottom surface allows contents of the container to enter the cavity portion behind the cover, the cover forming a second gap between the weir and the cover. A total cross-sectional area of the one or more openings, a second cross-sectional area of the second gap, and the first cross-sectional area of the first gap are substantially equal.

In another feature, the first cross-sectional area of the first gap is a maximum of 1500 square millimeters.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an overflow drain in accordance with the present invention;

FIGS. 2A-2B illustrate a perspective back and front view of an implementation of a weir;

FIGS. 3A-3B illustrate a perspective back and front view of an implementation of a cover;

FIG. 4 illustrates the assembly of the drain cover assembly to a bathtub;

FIG. 5 illustrates a top cutaway view of a drain cover assembly assembled to a bathtub; and

FIG. 6 illustrates a side cutaway view of a drain cover assembly assembled to a bathtub.

DETAILED DESCRIPTION

The present invention is an overflow drain cover assembly for covering all or part of an overflow drain in a container. The overflow drain in a container limits the level to which the contents of the container may rise by providing a controlled outlet for the contents when the contents rise above the lowermost point of the drain. In this manner, the overflow drain can avoid having the contents of the container from overflowing the edges of the container in an uncontrolled manner. The overflow drain cover assembly according to the present disclosure can raise the level to which the contents of the container may rise before draining through the overflow drain and maintain the function of avoiding the contents from overflowing the edges of the container.

FIG. 1 illustrates an overflow drain cover assembly 100 according to the present invention. An overflow drain 102 and overflow adapter gasket 104 are not part of the present invention and illustrated for completeness and context. The overflow drain cover assembly 100 includes an overflow hold ring or weir 106. The weir 106 may be made of any suitable material such as plastic or metal. Preferably the material is resistant to corrosion when subjected to fluids that are held in a container (not shown). A sealing gasket 108 is assembled between the weir 106 and the overflow drain/adapter gasket. The sealing gasket may be made of plastic, rubber, neoprene or other material to inhibit fluid flow around the weir 106 until the fluid level rises above a top of the weir 110. One or more mounting screws 112 can affix the weir 106 and gasket 108 to the overflow drain. Sealing gasket 108 and weir 106 can have through holes to permit passage of the mounting screws 112. Other mounting devices such as threaded studs and clips may be used to retain the weir and gasket against the overflow drain/adapter gasket. A cover 114 covers the weir and gasket to provide an aesthetically pleasing look. The cover 114 may have openings 116 on a bottom surface to permit the entry of fluid therein as the level rises in the container.

FIG. 2A-2B illustrate a perspective view of a weir 200 from the back and front views, respectively. The weir has a back surface 202 that, when assembled to a container, can rest against the vertical wall of the container. Weir 200 can have mounting holes 204 to accept screws for mounting the weir to the container. A sealing gasket (not shown) can be put between the weir and the container, in the area 206 for example, to enhance the seal between the weir back surface 202 and the container. In this way, fluid in the container is inhibited from getting past the weir until the fluid level in the container rises above a top of the weir 208.

FIG. 3A-3B illustrate a perspective view of a cover 300 from the back and front views, respectively. Cover 300 has one or more cover openings 302 in a bottom surface 306. Cover openings 302 each have a cross-sectional area 304. Fluid can enter the cover through the cover openings at a rate that is limited by the total of the cross-sectional areas 304. In one embodiment, the total cross-sectional area cover openings 302 a minimum of 1000 square millimeters and preferably a maximum of 1500 square millimeters.

FIG. 4 illustrates the assembly of one implementation of a drain cover assembly to a bathtub 402 having an overflow drain 404. The overflow drain has threaded mounting holes 418. In the illustrated implementation, a sealing gasket 408 has through holes 410 and a weir 406 has through holes 416. Gasket through holes 408 and weir through holes 416 are aligned with threaded mounting holes 418. Screws 412 are installed through the through holes 410, 416 and threaded into threaded mounting holes 418. Tightening screws 412 pressed the weir 406 against sealing gasket 408 and a vertical wall of the bathtub 402 inhibiting water in the bathtub from flowing into the overflow drain 404 until the water level rises above a top of the weir 420. A cover 414 is adapted to fit over and attach to the weir 406.

FIG. 5 illustrates a top cutaway view of an overflow drain cover assembly assembled to a vertical wall 502 of a bathtub having an overflow drain 504. A weir 506 is mounted to the overflow drain 504 as described above. A front surface 516 of the weir is spaced away from the vertical wall 502 of the bathtub creating a first gap 518. A cross-section area of the first gap is represented by the cross-hatched area 520. In one embodiment, the cross-sectional area 520 of the first gap is a minimum of 1000 square millimeters and preferably a maximum of 1500 square millimeters.

A cover 514, shown in cutaway view, covers the weir creating a second gap 522 therebetween. A cross-section area of the second gap is represented by the cross-hatched area 524. In one embodiment, the cross-sectional area 524 of the first gap is a minimum of 1000 square millimeters and preferably a maximum of 1500 square millimeters.

FIG. 6 a side cutaway view of the overflow drain cover assembly assembled to a vertical wall 602 of a bathtub having an overflow drain 604. Weir 606 is mounted to a vertical wall 602 of a bathtub. A sealing gasket 608 is between weir 606 and vertical wall 602. Cover 614 covers the weir as described above. An arbitrary level of water 620 is illustrated as being in the tub. As the level 620 rises in the bathtub, openings 616 in cover 614 permit water to enter behind the cover into the cavity between the cover and the weir. Sealing gasket 608 between the weir 606 and the vertical wall 602 inhibits water from entering the overflow drain 604 until the water level rises above a top 610 of the weir.

Thus, the overflow drain cover assembly raises the level of water in the tub from the bottom of the overflow drain to the top of the weir. This allows for more water in the bathtub and deeper water for the user. The top of the weir is above the bottom of the overflow drain and has the opening gap at the top of the weir. This allows the waterline in the tub to fill to a higher level before it spills over weir into the overflow drain. The water enters the bottom of the overflow cover through the openings in the bottom of the cover and fills up the inside of the overflow assembly until it reaches the top of the weir. The openings in the bottom of the cover allow water to enter and flow up and into the overflow hole. The sealing gasket on the back side of the weir prevents water from entering the overflow drain until the water has reached the top of the weir. With this overflow drain cover assembly installed, the user can fill the bathtub to a higher level and experience a deeper immersion of the user's body in an existing bathtub shape.

In an embodiment, the cross sectional area of the cover opening at the bottom of the cover, the cross sectional area of the second gap between the cover and the weir and the cross sectional area of the first gap between the top of the weir and the overflow drain are the same. The larger the cross-sectional area of these three sections, the larger the volume of water flowing into the overflow drain. The upper limit of that flow rate area is reached when the cross sectional area of any of the three opening is equal to the cross sectional area of the overflow drain pipe diameter.

Other embodiments of the present invention are within the scope of the following claims. 

1. An overflow drain cover assembly, comprising: a weir having a cavity portion, the cavity portion forming a gap at a top of the weir when the weir is mounted to an overflow drain on a substantially vertical wall of a container, wherein the weir blocks contents of the container below the top of the weir from entering the overflow drain, and wherein a first cross-sectional area of the first gap is a minimum of 1000 square millimeters.
 2. The overflow drain cover assembly of claim 1, comprising: a gasket between the weir and the vertical wall, the gasket enhancing a seal between the weir and the vertical wall when the weir is mounted to the overflow drain.
 3. The overflow drain cover assembly of claim 2, comprising: a cover covering the weir and having one or more openings on a bottom surface to allow contents of the container to enter behind the cover, the cover forming a second gap between the weir and the cover, wherein a total cross-sectional area of the one or more openings, a second cross-sectional area of the second gap, and the first cross-sectional area of the first gap are substantially equal.
 4. The overflow drain cover assembly of claim 3, wherein a first cross-sectional area of the first gap is a maximum of 1500 square millimeters.
 5. The overflow drain cover assembly of claim 4, wherein the cover is mounted to the weir.
 6. The overflow drain cover assembly of claim 4, comprising one or more mounting devices capable of mounting the weir to the overflow drain.
 7. The overflow drain assembly of claim 6, wherein the weir has through holes and the one or mounting devices are screws that fit through the through holes.
 8. A method of raising contents of a container above the level of an overflow drain; comprising: mounting a weir to the overflow drain, the weir having a cavity portion, the cavity portion forming a first gap at a top of the weir when the weir is mounted to the overflow drain on a substantially vertical wall of the container, wherein the weir blocks contents of the container below the top of the weir from entering the overflow drain, and wherein a first cross-sectional area of the first gap is a minimum of 1000 square millimeters.
 9. The method of claim 8, comprising: providing a gasket between the weir and the vertical wall, the gasket enhancing a seal between the weir and the vertical wall when the weir is mounted to the overflow drain.
 10. The method of claim 9, comprising: covering the weir with a cover, the cover having one or more openings on a bottom surface thereof; forming a second gap between the weir and the cover; and allowing contents of the container to enter behind the cover through the one or more openings. wherein a total cross-sectional area of the one or more openings, a second cross-sectional area of the second gap, and the first cross-sectional area of the first gap are substantially equal.
 11. The method of claim 10, wherein a first cross-sectional area of the first gap is a maximum of 1500 square millimeters.
 12. The overflow drain cover assembly of claim 11, comprising mounting the cover to the weir. 